This invention relates to a covering device generally applicable to any box-shaped unit including, but not limited to, loaded and unloaded open cargo areas of trucks and trailers. More particularly, this invention concerns an improved overhead, sliding, reinforced and motorized covering device.
The necessarity for these covers has resulted in part from local and state highway regulations that require trucks and trailers which haul material such as sand, gravel, land fill, and refuse to have the top of the open body of the loaded truck and trailer covered with a tarpaulin-type device. Past practice has been for the truckers to carry the tarpaulin in a convenient location. When the truck is load, it is necessary to manually spread this tarpaulin over the load. The tarpaulin must then be tied down minimally at its four corners to secure it in position. This is a time consuming process that a hazardous when the truck surfaces are climbed upon and more so when said surfaces are wet and slippery. In large trucks and trailers, it should be remembered that the top of the truck body is some nine feet above the ground. Therefore, it is desirable that automatic means be provided to obviate the need for the trucker to climb upon the body of the truck to pull a tarpaulin over the loose load. Recent developments have produced some devices that mechanicaly extend and rtract the tarpaulin in the operation of covering the open body of the truck. However, with one exception, all of these devices still retain the safety hazards of requiring that the operator get out of the truck to tie down the tarpaulin.
Earlier covering devices have further shortcomings. Firstly, they are easily ripped or torn, which requires their periodic replacement. Secondly, due to their sagging nature, they may often be soiled or contaminated by the cargo transported, which also requires their periodic replacement. Thirdly, they may often be thrown off the truck by high winds or high speeds of the truck. Fourthly, they do not effectively completely cover the cargo, which may lead to loss of cargo during transport, or cause air pollution, as when items such as coal, sand, dirt or other substances capable of airborne distribution are transported. In addition, the load may be of light weight absorbent material, such as wood chips, which will retain rainwater and become considerably more costly to haul in terms of weight and load spoilage. Fifthly, substantial down-time is required of the driver, truck, and trailer in order to cover and uncover truck and trailer cargo areas. Sixthly, due to inadequacy of existing covers in addition to the aforementioned down-time, truck and trailer cargo areas are not covered when empty thereby causing extreme in-transit aerodynamic drag resulting in excessive fuel consumption and earlier engine failure.
Similar problems are encountered in other open top transportable cargo compartments such as railroad cars, containers for shipboard or aircraft loading, and refuse collecting bins which are parked until filled, then transported. In general, such cargo compartments are of rectangular configuration, and most are equipped for wheeled transportion.
Accordingly, it is an object of the present invention to provide an improved covering device for transportable open top cargo compartments of rectangular configuration, said device being automatically deployable.
It is another object of the present invention to provide a covering device as in the foregoing object comprising an assembly which affords a reinforced overhead covering for effectively sealing the cargo compartment of a truck or trailer.
It is a further object of the present invention to provide a covering device of the aforesaid nature of durable construction and amenable to low cost manufacturers.
It is an additional object of the present invention to eliminate any driver, truck and trailer down-time related to the covering and uncovering of cargo areas.
It is yet another object of the present invention to provide a covering device of the aforesaid nature which will increase the aerodynamic efficiency of trucks and trailers by covering their cargo compartments whether loaded or empty.